steel Column verification and design

[Michele100100]

Hello,

I have a problem with design of a steel column: Robot doesn't take the maximum value of Forces for the design? Why?

It happened sometimes, and I need always to imput manually values...There is anyway to do it automatically?

In the model attached, column n. 5 have different values of maximum forces:

Combination 1to62, I read N = 30, Fy = 22.31KN, Fz = 20,90KN, My = 25.88KNm and Mz = 17.43 KNm, very different from the design table results. Why? Where I'm wrong? Any help? thanks

[Krzysztof_Wasik · Accepted solution]

Hi @Michele100100 

You probably found extreme forces in forces table.

Robot checks each load case separatelly, while your values are taken from different load cases (12 and 13)

Also maximum force value (in point 1) can cause smaller capacity ratio than in pint (2)  if in this  point force is smaller but buckling/leteral buckling length is bigger.

[Michele100100]

Hello, thanks for the fast reply. 

So Robot take the worst combination and not using envelope of all combinations. 

Thanks